1. Field of the Invention
The invention relates to a connection arrangement for clamping a cylinder head to a crankcase of a reciprocating internal combustion.
2. Description of the Related Art
In marine diesel internal combustion engines, as well as other internal combustion engines, it is already known as disclosed in DE 10 2005 020 588 A1, to connect assemblies of said engines using several tension rods and to provide a compression preload in the interconnected assemblies via the tension rods. In the case of marine diesel internal combustion engines, a crankcase is preferably connected to a cylinder head via several tension rods.
Tension rods possess an external thread via which the tension rods are connected to one of the assemblies to be interconnected. Specifically, the tension rods are screwed into undercuts of the assembly having an internal thread. In the case of internal combustion engines the thread of each tension rod has to be protected against a corrosive attack by a corrosive medium to guard against a fracture of the tension rod. Sealing devices are associated with the tension rods to prevent the corrosive medium from contact with the tension rod.
Cylinder head tension rods are screwed into the crankcase as deep as possible to subject the casting to compression preload. During engine operation, the cylinder head tension rods are generally surrounded by an oil mist. Through temperature change, water condensation in the crankcase occurs. This water must not come in contact with the thread flanks of the tension rods. As already mentioned, a fracture of the tension rods can result due to corrosion from the water condensation.
Typically, sealing devices associated with the tension rods in internal combustion engines are embodied as O-rings arranged in a slot on each respective tension rod. The condensate is kept away from the thread by means of the O-ring. However, the slot to accommodate the O-ring causes notch stresses in the tension rod, as a result of which the tension rod can fracture during operation.